A Polygon is made of a set of Vertices, and each Vertex points to a Point.
Some Vertex Attributes
||float||4||Surface color and alpha specified by RGBA. Values range from 0 to 1. The alpha component Cd(3) controls the transparency of a given element, where 1 is fully opaque, and 0 is fully transparent.|
||float||1||Crease weights, use in sub-division surfaces. See Subdivide SOP.|
||float||2||Capture data containing index and weight for a transform. See Deforming Geometry (Skinning)|
Each SOP has a list of Points. Each point has an XYZ 3D position value plus other optional attributes. Each polygon Primitive is defined by a vertex list, which is list of point numbers.